During the weekend, the weather got worse with winds up to 7 Beaufort and on Saturday no fishing activity happened. This was also caused by the lack of interesting fish aggregations in the echogram. On Sunday, two hauls were performed with herring present in the late morning (haul 24). The haul was performed on Sunday 19 July at 11:04 UTC at 55.37.36 N - 1.50.42 E where 3476 kg of fish was caught with 0.9 kg of Herring, but most of the catch was whiting (1229.6 kg) and haddock (2372.9 kg).
Haul 24 on Sunday 19 July at 11:04 UTC at 55.37.36 N - 1.50.42 E 1229.6 kg of whiting, 2372.9 kg of haddock and 0.9 kg of herring.
The weather improved on Monday 20 July and two hauls were performed with mostly mackerel in the net. Haul 26 at 18:30 UTC at 55.12.31 N - 0.43.02 E had a total catch of 252.4 kg with 197.5 kg of mackerel, 21.9 of whiting and 33,1 kg of haddock.
Subsample of catch 26 showing that the haul had mostly mackerel.
On Tuesday 21 July two hauls were performed, with the first one in the morning and the second one in the afternoon. In the first one (haul 27) at 12:05 UTC at 55.7.01 N - 3.26.90 E, a porbeagle was present, and the catch was mostly mackerel with 86.3 kg. The second haul (28) at 16:19 UTC at 55.7.35 N - 4.7.71 E was a very large catch of herring of different sizes, for a total catch of 5.2 kg of herring, 37.3 kg of sprat, 16.6 of whiting and 11.4 kg of haddock.
Haul 27 on 21 July 2026 at 12:05 UTC at 55.7.01 N - 3.26.90 E with a total catch 86.3 kg of mackerel.
Porbeagle in haul 27.
The last haul (29) at 05:40 UTC at 55.7.51 N - 5.29.74 E of the trip was performed on Wednesday morning and contained 47.5 kg of mackerel. The rest of the day, Tridens steamed back to Scheveningen for an arrival on Thursday morning. Late in the evening, Tridens collected some acoustic data from seabed reflection that is used yearly to calibrate PFA fishing vessels. To gain more information on the stability of the signal, Tridens passed over the location three times and multibeam data was also collected.
Below can be seen summary plots of the 4-week surveys where 37 CTDs and 29 trawls were performed, starting from the North of Scotland and ending in the middle of England.
Summary of all the CTDs performed during the 4-week survey.
Summary of all the trawls performed during the 4-week survey.
After the scrutiny of the echosounder data, we also created summary maps of the Nautical Area Scattering Coefficient (NASC) for each species (whiting, haddock, herring, sprat and pout). The NASC can be used as a proxy for biomass and helps understand the distribution of different species. Generally, it can be seen an increase in the whiting presence from north to south and the presence of pout was only in the northern region. Instead, sprat was present just in the final part of the survey in the south-east region. Haddock was present during the entire survey and herring had its major presence in a couple of hauls in the centre-east region of the survey.
Summary of the NASC for whiting.
Summary of the NASC for haddock.
Summary of the NASC for herring.
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